Spring hinges are a great addition to any pair of eyeglasses. They let the temples (the long arms that rest on your ears) flex outwards, so that the glasses adjust to the shape of the head. This helps the glasses stay in place and makes them easier to wear for many people.

It isn’t all positive, however. Eyeglasses with spring hinges are more difficult to repair, and unless the spring hinges are of good quality, they are often the first thing to break in the glasses. Because of the way the hinges work, tightening or replacing a missing temple screw can be a tricky affair.

In this article I will explain how eyeglasses spring hinges work, why it is difficult to replace the small temple screws, and show you how to fix loose or missing screws yourself at home.

What is a spring hinge on glasses?

Spring hinges, also known as flex hinges, contain a small spring that lets the arms of glasses extend further than other types of hinges do. With traditional barrel hinges, the movement is usually limited to 90°. With spring hinges, however, you can move the arms out a lot further.

A pair of glasses with spring hinges that extend further than the traditional 90 degrees of barrel hinges.

The benefits of spring hinges is that they provide more comfort, help the glasses stay on during physical activity, and require less adjustments than traditional hinges.

How does a spring hinge work?

Spring hinges use a spring-loaded plunger mechanism that is placed on or even inside of the temple (arm) of the glasses. When the temple is extended further outwards than its resting position, the tension on this mechanism pulls the arm back inwards.

In practice, this creates a snug fit that lets you know your glasses are always there.

What makes it difficult to fix a loose or missing screw on a spring hinge?

Because of the mechanism described above, when the small temple screw is not or only partially inserted, the plunger retracts into the mechanism because of the spring. The barrel hole on the temple is attached to the plunger, so this causes the hole to misalign with the other hole on the glasses frame.

A close-up of misaligned holes on a spring hinge.
Misaligned holes on a spring hinge. You’ll notice that there is no perfectly round path for the screw to go through.
A close-up of properly aligned holes on a spring hinge.
This is what the hinge is supposed to look like to be able to drive the screw in.

When you try to drive the temple screw in when the hole is not lined up, you just end with a misaligned screw that can not be screwed in all the way, like so:

A misaligned screw stuck in the spring hinge of a pair of Ray-Ban eyeglasses.

In order to properly drive the screw in and fix the temple to the frame, we must first align the holes. This can be done by extending the spring hinge by hand and then temporarily fixing it in place. I have described this process further down the page.

What do you need to fix the screw?

Not much, the most important things are a precision screwdriver and if necessary, a replacement screw.

The size of the screwdriver and screw depend on the exact glasses you have, but in most cases, a typical eyeglasses repair kit will have everything you need.

Can you fix the actual spring hinge if it is broken?

Unfortunately, no. The mechanism is quite small and intricate, and repairing it yourself when it is damaged is near impossible. You’ll need to go to an optician or eyeglasses repair company for this.

An external spring hinge can be replaced without having to replace the temple, but to do that, a professional will need to detach the original and solder a new one in place.

You can recognize an external spring hinge by the fact that there is a visible bulge on the side of the temple that faces your head.

An internal spring hinge, on the other hand, can’t be repaired or replaced. Typically the entire temple needs to be replaced, because the replacement comes with a fully working spring hinge.

Internal spring hinges are integrated in the temple itself and are practically invisible. This looks a bit nicer, but is regrettably also harder to deal with when it is broken.

Does this repair guide also work for sunglasses?

Yes, you can use this guide for both regular eyeglasses and sunglasses, as long as they have a spring hinge. You’ll typically find these on Ray-Ban glasses, but as far as I can tell, it should work on any pair of glasses with this type of hinge.

What about glasses with standard barrel hinges?

On glasses with standard barrel hinges, you won’t need to extend the hinge first. You can just screw a replacement temple screw in, or tighten it, if it is loose. Provided that the hinge is fully functional and not damaged, of course.

How to reattach a loose or missing screw on a spring hinge – Step-by-step

Required materials & tools

  • Replacement temple screw (in case of a missing one)
  • Precision screwdriver that matches the screw head
  • One or two paper clips or push pins

Usually you can find everything you need (aside from the paper clips/push pins) in an eyeglasses repair kit.

A pair of broken Ray-Ban glasses with a detached loose temple arm.
To start, make sure that the temple (arm) is fully detached from the glasses. So if the screw is still partially stuck in the hinge, you need to remove it first.
The hole of a glasses hinge placed on a screwdriver bit in order to open it.
Hook something onto the hole of the spring hinge. I used a precision screwdriver bit that was placed in a vise, but you can also use a push pin or paper clip that you hold with your other hand. The method you see worked best for me, because I needed a free hand to make pictures.
A precision screwdriver bit being used to extend a spring hinge.
Pull the temple radially outwards with your hand until the hinge extends. This might take a bit of force. Once the hinge is opened far enough, you will see a small gap opening up on the inside of the temple.
A paperclip being inserted into the extended spring hinge of the temple of a pair of Ray-Ban glasses.
Stick a paper clip or push pin into the gap that just opened. This will keep the spring hinge extended without having to keep pulling on it.
Warning icon
If the paper clip/push pin is too thick, you need to either sand it down a bit, or use something thinner like a needle.
Make sure that you don’t use something fragile like a toothpick, because you don’t want it to break off and get stuck in the hinge mechanism.
A spring hinge fixed in an extended position through the use of a paperclip.
If you now release the side of the temple with the hole, the hinge should stay in its extended position by itself.
A temple (arm) of a pair of glasses properly aligned with the frame hinge.
Line the temple up with the frame of the glasses.
A pair of pliers being used to drop a temple screw into a spring hinge.
Place the small screw into the hinge hole. I used a pair of tweezers for this, put you can also do this with your fingers as long as you are careful.
Info icon
Once you start handling small screws, it can help to work on a clean, single-colored work surface. That way, if the screw tries to escape, you can find it more easily. One way of doing this is by placing several sheets of blank A4 paper on your desk or table.
A precision screwdriver driving a screw in a glasses hinge
Use your precision screwdriver to drive the screw all the way into the hinge. If the holes of the hinge are properly aligned, you should not feel much resistance during this step.
A paperclip being pulled out of the spring hinge of a pair of glasses.
Once the screw is set, remove the paper clip/push pin. Your glasses are now fixed and ready to get back to action!

A summary of the repair process

  1. Fully separate the temple (arm) from the frame of your eyeglasses.
  2. Hook the hole of the spring hinge onto something that will give you extra grip.
  3. Pull on the temple to fully extend the spring hinge.
  4. Insert a paper clip or push pin into the gap that opened to keep the hinge in its extended position.
  5. Take the temple and align it with the glasses frame.
  6. Carefully drop the small temple screw into the hinge.
  7. Use a precision screwdriver to drive the screw and secure the temple to the frame.
  8. Remove the paper clip or push pin that you used to keep the hinge open.

Conclusion

Once you know how the spring hinges on your eyeglasses or sunglasses work, it isn’t too hard to tighten a loose screw or even to replace a missing one. The trick is to extend the plunger of the hinge, and fix it in place before attempting to drive in the screw. If you don’t do this, the screw ends up misaligned and can not be driven all the way in.

Unfortunately, it isn’t possible to repair a broken spring hinge. Only a professional can do that for you. At best, you can replace the entire temple by yourself. If you manage to find a matching replacement temple and follow this guide to reattach it to the frame of the glasses, they should be as good as new.

Info icon
If you would like to do the maintenance of your own glasses, you might be interested in knowing how to clean them professionally at home. You can do this with an ultrasonic cleaner. They don’t cost much and give you consistent professional cleaning results in only a few minutes!

You learned:

  • What a spring hinge is.
  • How a spring hinge works.
  • How to replace or tighten a screw on the screw hinges of your glasses.

If you find this article useful, please share it or leave a comment. I love to hear your feedback and questions!

Sources:

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top